yes burn in can be placebo (although not in the case of the 101s) and even when it does happen its extremely marginal. Also burn in is not necessarily a good thing, phones can sound great out the box and deteriorate through more hours. More people need to know this.

Can someone describe the treble on the Sony Sony MDR-XB90EX?. I really like my treble and I'm curious since a lot of the time Sony tends to roll-off their treble compared to many Audio-Technica and Beyerdynamic headphones.

yes burn in can be placebo (although not in the case of the 101s) and even when it does happen its extremely marginal. Also burn in is not necessarily a good thing, phones can sound great out the box and deteriorate through more hours. More people need to know this.

Yeah, I agree ! ...the HA S400 sound great out of the box, I had to go and burn them !!!

50hrs later and they sound like Beats ...almost threw them into the dustbin.

Thanks god I didn't because 100hrs+ later ...they became my all time favourites !

just wanted to chime in about all this burn-in paranoia :D If you listen to the music, then you are burning in the iems, so no use discussing the pros and cons of burn in - you want it or not, you are still gonna burn them in, so enjoy what you got and don't panic :P also, burn in works and no, it is not a placebo - the difference is too big and noticeable. also, measurable, when compared against unused iems...

Can someone describe the treble on the Sony Sony MDR-XB90EX?. I really like my treble and I'm curious since a lot of the time Sony tends to roll-off their treble compared to many Audio-Technica and Beyerdynamic headphones.

I'm curious about this too. One of the things I like most about the FX101 is the highs.

There is a bit of roll off on the XB90EX however I noticed especially after a good burn in. The highs are actually very good. It does not have the extended highs that are in the more detailed oriented earphones. The Carbon nanotube earphones for one. However I feel it makes up for this lack of top end sparkle with endless deep sound that are an EX specialty..If you guys want your highs with your mids and bass. While the sound is not as tight the CKS77 is actually this..This bit of roll off makes the earphones sound very smooth and tunes are ultimately very easy to listen to. Imagery is also very nice on the XB90. Recordings with up front vocals are clearly heard up front and center. Many earphones can't convey the position of instruments to vocals and the depth required for this to be right but the XB90 is magical with it comes to this making big bands and live concerts a pleasure to listen to.